title: Exposure to electrical contact currents and the risk of childhood leukemia.
abstract: The objectives of this study were to examine the association between contact current exposure and the risk of childhood leukemia and to investigate the relationship between residential contact currents and magnetic fields. Indoor and outdoor contact voltage and magnetic-field measurements were collected for the diagnosis residence of 245 cases and 269 controls recruited in the Northern California Childhood Leukemia Study (2000-2007). Logistic regression techniques produced odds ratios (OR) adjusted for age, sex, Hispanic ethnicity, mother's race and household income. No statistically significant associations were seen between childhood leukemia and indoor contact voltage level [exposure ≥90th percentile (10.5 mV): OR  =  0.83, 95% confidence interval (CI): 0.45, 1.54], outdoor contact voltage level [exposure ≥90th percentile (291.2 mV): OR  =  0.89, 95% CI: 0.48, 1.63], or indoor magnetic-field levels (>0.20 µT: OR  =  0.76, 95% CI: 0.30, 1.93). Contact voltage was weakly correlated with magnetic field; correlation coefficients were r  =  0.10 (P  =  0.02) for indoor contact voltage and r  =  0.15 (P  =  0.001) for outdoor contact voltage. In conclusion, in this California population, there was no evidence of an association between childhood leukemia and exposure to contact currents or magnetic fields and a weak correlation between measures of contact current and magnetic fields.
authors.affiliation: School of Public Health, University of California, Berkeley, Berkeley, California, USA. modoes@berkeley.edu
authors.forename: Monique
authors.initials: M
authors.lastname: Does
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Scélo
authors.forename: Catherine
authors.initials: C
authors.lastname: Metayer
authors.forename: Steve
authors.initials: S
authors.lastname: Selvin
authors.forename: Robert
authors.initials: R
authors.lastname: Kavet
authors.forename: Patricia
authors.initials: P
authors.lastname: Buffler
mesh_terms: D002648:Child; D002675:Child, Preschool; D004553:Electric Conductivity / Q000009:adverse effects*; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D007938:Leukemia / Q000453:epidemiology* / Q000209:etiology*; D008280:Magnetics; D008297:Male; D012306:Risk